Shenzhen Engineering Laboratory for Eco-efficient Recycled Materials, School of Environment and Energy, Peking University Shenzhen Graduate School, University Town, Xili, Nanshan District, Shenzhen, 518055, PR China.
Shenzhen Engineering Laboratory for Eco-efficient Recycled Materials, School of Environment and Energy, Peking University Shenzhen Graduate School, University Town, Xili, Nanshan District, Shenzhen, 518055, PR China.
Chemosphere. 2023 Dec;344:140435. doi: 10.1016/j.chemosphere.2023.140435. Epub 2023 Oct 11.
Biofilm formation on plastic surface is a growing concern because it can alter the plastic surface properties and exacerbate the ecological risk. Identifying key factors that affecting biofilm formation is critical for effective pollution control. In this study, the poly (ethylene terephthalate) (PET) was aged in water and air conditions with UV irradiation, then incubated in the digestate of food waste anaerobic digestion to allow biofilm formation. Surface analysis techniques, including scanning electron microscopy (SEM), atomic force microscopy (AFM), and Fourier-transform infrared spectroscopy with attenuated total reflection (FTIR-ATR), were utilized to investigated the changes in the topography, roughness, hydrophily, and functional groups change of the PET surface during the aging process. Confocal laser scanning microscopy (CLSM) was used to determine the distribution of microorganisms on the PET surface after incubation in the digestate. This study focused on understanding the interactions between the PET surface and biofilm to identify critical surface factors that affect biofilm formation. Results showed that the four months aging process decreased the contact angle of the PET surface from 96.92° to 76.08° and 68.97° in water and air conditions, respectively, corresponding to an increase of 44% and 70% in the surface energy. Additionally, aging in air conditions led to a rougher surface compared to water conditions. The arithmetic roughness average (Ra) of the PET-Water was 11.0 nm, comparable to that of the pristine PET, while the value of PET-Air was much higher (43.9 nm). The results further indicated that biofilm formation during anaerobic digestion was more sensitive to roughness than hydrophily. The PET surface aged in air conditions provided a more suitable environment for microbial reproduction, leading to the aggradation of living cells.
塑料表面生物膜的形成是一个日益严重的问题，因为它会改变塑料表面的性质，并加剧生态风险。确定影响生物膜形成的关键因素对于有效的污染控制至关重要。在这项研究中，聚对苯二甲酸乙二醇酯（PET）在水和空气条件下进行老化，并进行紫外线照射，然后在食物废物厌氧消化的消化物中孵育，以允许生物膜形成。利用扫描电子显微镜（SEM）、原子力显微镜（AFM）和衰减全反射傅里叶变换红外光谱（FTIR-ATR）等表面分析技术，研究了 PET 表面在老化过程中形貌、粗糙度、亲水性和官能团变化的变化。共焦激光扫描显微镜（CLSM）用于确定在消化物中孵育后 PET 表面上微生物的分布。本研究重点研究了 PET 表面与生物膜之间的相互作用，以确定影响生物膜形成的关键表面因素。结果表明，四个月的老化过程使 PET 表面的接触角从水和空气条件下的 96.92°分别降低到 76.08°和 68.97°，相应的表面能分别增加了 44%和 70%。此外，在空气条件下老化会导致表面比水条件下更粗糙。PET-Water 的算术平均粗糙度（Ra）为 11.0nm，与原始 PET 相当，而 PET-Air 的值则高得多（43.9nm）。结果进一步表明，厌氧消化过程中的生物膜形成对粗糙度比对亲水性更敏感。在空气条件下老化的 PET 表面为微生物繁殖提供了更适宜的环境，导致活细胞的堆积。
